Hi robz,
Your last post poses a question- what do you want to do with the 16"? Visual or photo? Reason being, if for photo, man, you are going to need a BIG mount.
Yes, the larger the apeture, be finer resolution you can obtain. But ultimately it comes down to what is both practical and financially viable.
There are many folks who do planetary imaging with 8", 10" and 12" newt's. Mounts for these are tried and tested, and with quality barlows, provide excellent imaging quality. If you did go down the refractor route, you would still be needing a quality barlow to achieve the necessary magnification.
So where do you want to go, 4" refractor or 10" newtonian for imaging? Similar focal length, but markedly differing resolution.
If money is not an option, you have the 16" Meade SCT!
If visual is more your thing, a 16" dob is still a good option. If you could get the retailer to examine the thing before dispatching it, you are also on a winner with that fellow for service, who ever they may be. Something you may be able to insist on to overcome the tyrany of distance.